Today chess.com did an interview with Carlsen's coach.
Someone like Carlen or Anand, why do they still need coaches? Their Elo is higher than their coaches, they can use engines to analyze the games, and they can beat their coaches in practically every game, obviously they know more openings than anyone in their room.
I understand that someone hires a coach to get better, or in other sports you do that to stay in shape, but this is chess and there are computers if you need help, i guess all the coaches use them, so why hiring them? What is their major role? Do all GM's have coaches? (including the ones who died, Fischer, Capablanca etc).